One thing to note though is that the Firefox guys consistently show benchmarks of their latest code against stable, released versions of other browsers. If you filter out the drumroll what's left is a claim that says the browser we are going to realease will be as fast as the browser you have released months ago.

Wrong. Hover the graphs. They use latest builds of safari and chrome (or nitro and V8 if you want).

As of now, Chrome runs circles around Firefox in various performance benchmarks. Try peacekeeper, for instance: google "peacekeeper browser benchmark" - FF on my system gets 36xx score while Chrome gets 9001! We have this

We all know that FF is currently a bit slow. The question is, will FF4 be back among the others ? It seems that it might be the case. And the worst is that in the end, it does not matter : as a user, what's most important is not page rendering speed, it's UI responsiveness, and no benchmark currently measures this. E.g : IE7&IE8 take several seconds to open a tab when under load, FF3.5 was about as bad, though a bit faster (don't remember about 3.6), and on all other browsers the process is instant.